Russian President Vladimir Putin vowed a decisive response on Thursday to any country threatening Russia, and lashed out against Germany for promising tanks to Kyiv.
His threats came after Ukrainian President Volodymyr Zelensky alleged that the Kremlin was consolidating its forces for a fresh offensive.
Zelensky was speaking in Kyiv beside the European Union's chief Ursula von der Leyen, who said the bloc was looking to finalize fresh sanctions against Russia by Feb 24, exactly one year after the conflict broke out.
At a ceremony commemorating the Red Army's victory against Nazi troops 80 years ago in the southern Russian city of Volgograd, Putin said it is unbelievable that Russia is once again being threatened by German tanks.
"We have something to respond with," he said. "A modern war with Russia will be completely different."
Ukraine secured promises from the West this month for deliveries of modern battle tanks to fight Russian forces, and Kyiv is now asking for long-range missiles and fighter jets.
Putin has insisted that Russia is weathering the barrage of sanctions imposed by Ukraine's Western allies and will continue its special military operation in Ukraine.
But von der Leyen said sanctions were already "eroding" Russia's economy, "throwing it back by a generation". She estimated that an existing oil price cap alone was costing Moscow around 160 million euros ($174 million) every day.
Key summit
"We will introduce with our G7 partners an additional price cap on Russian petroleum products and by the 24th of February ... we aim to have the 10th package of sanctions in place," she said.
Von der Leyen arrived in Kyiv on Thursday with the bloc's most senior diplomat, Josep Borrell, ahead of a Ukraine-EU summit on Friday in Kyiv, which is seeking EU membership.
Zelensky said his country deserved to start accession talks this year to "give energy and motivation to our people to fight".
But EU leaders said the process could take many years.
Russian Foreign Minister Sergey Lavrov claimed the EU, and specifically von der Leyen, had called for Russia to be defeated, so its economy would be devastated.
"Is this not racism, not Nazism?" Lavrov said.
Lavrov's comments echoed Putin, who has frequently drawn parallels between what he calls Moscow's special military operation in Ukraine and the Soviet war against Nazi Germany.
Moscow launched the military operation last year, saying that Russia needed to "denazify" Ukraine.
Von der Leyen's trip also came one day after Kyiv raided the homes of an oligarch and public officials, as part of efforts to ease Western concerns about graft.
"I'm comforted to see that your anti-corruption bodies are on alert and effective," von der Leyen said.
